A metal ball of mass 0.1 kg is heated upto $500^{\circ} \mathrm{C}$ and dropped into a vessel of heat capacity $800 \mathrm{JK}^{-1}$ and containing 0.5 kg water. The initial temperature of water and vessel is $30^{\circ} \mathrm{C}$. What is the approximate percentage increment in the temperature of the water? [Specific Heat Capacities of water and metal are, respectively, $4200 \mathrm{Jkg}^{-} { }^1 \mathrm{~K}^{-1}$ and $\left.400 \mathrm{Jkg}^{-1} \mathrm{~K}^{-1}\right]$